This paper introduces a planning model to estimate the total distance traveled by prime movers in transporting import and export containers between a port, warehouses, and container yards. The total distance includes the empty trip distances traveled by the prime movers, which occur between jobs of towing containers. As the actual data of empty trips and their distances are often difficult to obtain, the gravity model has been used in the estimation process. This model has been applied to estimate the total distance traveled by all of the prime movers in Singapore, based on the existing container volume, port locations, terminal capacities, land use pattern, and road network. Comparison has also been made with a hypothetical scenario where all of the port operations are consolidated into a single terminal. The results show that, if the container ports near the central business district are shifted to a megaterminal nearer to the major industrial zones, approximately 4.9-6.8% savings in the total distance traveled could be achieved.